Set of floor panels and method for installing this set of floor panels

ABSTRACT

A set of floor panels, which is suitable for forming a floor covering in herringbone pattern, wherein these floor panels are oblong rectangular; wherein the long and the short edges are provided with mechanical coupling means; and wherein the male coupling part on the short edge can be inserted into the female coupling part on the long edge in one and the same turning movement which is used to insert the male coupling part on the long edge into the female coupling part on the long or short edge.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a set of floor panels which is suitablefor forming a floor covering, as well as to a method for installing thisset of floor panels.

In particular, the invention relates to a set of floor panels which issuitable for forming a floor covering in herringbone pattern.

The floor panels are oblong rectangular and thus comprise a pair of longedges and a pair of short edges. The long as well as the short edges areprovided with mechanical coupling parts which allow coupling the floorpanels to each other.

Moreover, the set consists of at least two types of floor panels,wherein the coupling parts of the one type of floor panels on one pairof edges are mirrored in respect to the coupling parts of the other typeof floor panels at that same pair. Or, more explicitly, this relates tothe location of these coupling parts which is mirrored.

2. Related Art

Such set of floor panels is known as such from, amongst others, thedocuments WO 2004/063491 A1 and WO 2005/054599 A1.

WO 2004/063491 A1 primarily is directed to the use of coupling parts onthe pair of short edges which are of the same type as the coupling partson the pair of long edges. For example, on the long as well as on theshort edges coupling parts are applied which can be joined into eachother by means of a turning and/or shifting movement. A disadvantagethereof is that the installation of the floor panels in herringbonepattern is not always performed equally smooth.

However, in WO 2004/063491 A1 it is also noted that on the pair of shortedges coupling parts can be applied having another configuration thanthe coupling parts on the pair of long edges. For example, on the pairof short edges coupling parts can be applied which can be joined intoeach other by means of a downward movement, whereas on the pair of longedges coupling parts are applied which fit into each other by means of aturning movement. In this case, however, from WO 2004/063491 A1 it isnot clear at all how the floor panels then can be installed in aherringbone pattern.

WO 2005/054599 A1 indeed shows a manner for installing floor panels,which are provided on the pair of short edges with coupling parts whichcan be joined into each other by a downward movement, in a herringbonepattern. The manner described in this document allows coupling a floorpanel in a single turning movement on the long as on the short edge withadjoining, already installed floor panels, with a herringbone pattern asthe result. In the technical field, the single turning movement is alsoindicated by the term fold-down movement. However, the disclosed floorcovering shows the disadvantage that among the mutually coupled floorpanels a substantial risk of the occurrence of height differences ispresent. These height differences are undesired, in view of the factthat primarily they are not visually attractive. Apart therefrom, they,for example, also cause the upper edges of the floor panels to show wearfaster there, where these height differences are present. These upperedges then in fact are exposed to exterior influences. The describedfloor covering also shows the disadvantage that, with dimensionalchanges in the floor panels, a significant risk of the formations ofgaps or cracks or even a risk of floor panels sticking up may bepresent.

In FIG. 6 of WO 2005/054599 A1, a locking system is presented which isapplicable to the short edges of the floor panels. This locking systemmakes use of a separate insert. However, from WO 2005/054599 A1 it isnot clear at all how floor panels with such locking system then have tobe installed in a herringbone pattern.

SUMMARY OF THE DISCLOSURE

The present invention primarily aims at an alternative set of floorpanels, which is suitable for forming a floor covering in herringbonepattern. In particular, it is an aim of the invention to provide floorpanels which, on the one hand, can be smoothly installed in aherringbone pattern and, on the other hand, can be solidly coupled toeach other, such that the risk of height differences, the formation ofgaps or cracks between the mutually coupled floor panels can beminimized.

To this aim, the invention relates to a set of floor panels, which issuitable for forming a floor covering in herringbone pattern, whereinthese floor panels are oblong rectangular and thus comprise a pair oflong edges and a pair of short edges; wherein the long as well as theshort edges are provided with mechanical coupling means, which allowcoupling the floor panels to each other; wherein the one long edge isprovided with a male coupling part and the other long edge is providedwith a female coupling part; wherein the one short edge is provided witha male coupling part and the other short edge is provided with a femalecoupling part; wherein the male coupling part on the long edge can beinserted into the female coupling part on the long edge by means of aturning movement; wherein the male coupling part on the long edge canalso be inserted into the female coupling part on the short edge bymeans of a turning movement; and wherein the male coupling part on theshort edge can be inserted into the female coupling part on the longedge in one and the same turning movement which is used to insert themale coupling part on the long edge into the female coupling part on thelong or short edge; with the characteristic that the male coupling parton the short edge and the female coupling part on the long edge, in acoupled condition thereof, effect a locking in horizontal direction aswell as a locking in vertical direction.

The invention, on the one hand, offers the advantage that a floorcovering in herringbone pattern can be obtained in a smooth manner. Infact, the configuration of the floor panels allows coupling these floorpanels by means of the already above-mentioned fold-down movement andinstalling them in a herringbone pattern. A floor panel from the set canbe coupled at the same time with the long and the short edge to adjacentand already installed floor panels from the set. Preferably, the floorpanel then is coupled with the long and the short edge at least to thelong edges of the adjacent and already installed floor panels in orderto obtain a herringbone pattern. On the other hand, in the obtainedfloor covering the risk of height differences, the formation of gaps orcracks among the mutually coupled floor panels is minimized. In fact, agood locking is not only present among the mutually coupled long edges,but a solid locking can also be provided among the mutually coupledshort and long edges.

In a practical embodiment, the male coupling part on the short edgecomprises a first locking element, which, in a coupled condition of thismale coupling part and the female coupling part on the long edge,cooperates with a first locking element of this female coupling part inorder to effect said locking in vertical direction.

There, where the first locking elements cooperate with each other,preferably a tangent line is defined which runs upward in the directionaway from the respective female locking part. This tangent line thuspreferably is oriented inclined. The advantage of such cooperation isthat, even with minor profile deviations as a result of tolerancesoccurring when manufacturing the locking elements, it still can effectthe vertical locking. In other words, it allows compensating thesetolerances. Preferably, said tangent line forms an angle with thehorizontal which is smaller than or equal to 45 degrees.

The first locking element of the male coupling part can be realized fromthe material of the floor panel and in particular in one piecetherewith. This can be achieved, for example, by manufacturing thislocking element from the material of the floor panel by means of one ormore cutting tools or milling tools.

Better, however, the first locking element of the male coupling part isrealized as a separate insert.

The insert can be provided in a recess in the male coupling part on theshort edge. Preferably, the insert then is provided in the recess in aclamping manner by, for example, over-dimensioning this insert inrespect to the recess. In a particularly preferred embodiment, therecess is provided in a distal side or edge of the respective malecoupling part.

The use of the insert offers the advantage that the features thereof donot depend on the material of the floor panel. The insert can beconfigured such that it allows a smooth installation as well as a goodvertical locking, and this independent from the material characteristicsof the actual floor panel. The material of the insert preferablyconcerns synthetic material. Examples of synthetic material, which canbe applied to this end, are polyvinyl chloride, polypropylene,polyethylene or polyurethane. Further, the material of the insert, inorder to increase the strength thereof, may also comprise fibers. Forexample, mineral fibers, such as glass fibers, can be applied for thispurpose. The insert can be manufactured from one and the same material;however, this does not necessarily have to be so. So, the insert can becomposed of several materials, which, for example, mutually show adifferent flexibility. According to the function of the specific portionof the insert, this then can be made of a more or less flexiblematerial. A technique which can be applied for manufacturing the insertfrom several materials is coextrusion.

It is noted that such insert is known as such from, amongst others, thefollowing documents: WO 2005/054599 A1, WO 2008/068245 A1, WO2011/127981 A1 and WO 2013/118030 A2. The inserts described in thesedocuments can be applied in the present invention. More in general, anyinsert which is suitable for being applied for a fold-down type of floorpanel can be applied in the present invention.

Preferably, the insert comprises a locking part which, when performingthe coupling movement, arrives in a locking position by performing alateral movement. This lateral movement may concern, for example, alinear movement or a turning or rotational movement. Preferably, theinsert, or at least a portion thereof, is elastically deformable and/ordisplaceable in order to allow said lateral movement.

The lateral movement can be single or dual. In the single movement, thelocking part, during the coupling movement, is brought directly from aninitial position to a locking position, and this preferably according toa movement in only one a direction. In the dual movement, the lockingpart, during the coupling movement, is brought indirectly from aninitial position to the locking position, and this, for example, bybringing the locking part first according to a direction into anintermediary position and subsequently in the opposite direction fromthe intermediary position to the locking position.

The principle of the single lateral movement is known as such from,amongst others, the document WO 2011/127981 A1, whereas the principle ofthe dual lateral movement is known as such from, amongst others, thedocuments WO 2005/054599 A1 and WO 2013/118030 A2.

It is also noted that the male coupling part on the short edge can beprovided with a plurality of locking elements, which, in a coupledcondition with the female coupling part on the long edge, respectivelycooperate with a plurality of locking elements of the respective femalecoupling part. The cooperation of this plurality of locking elementsthen effects the vertical locking. The use of a plurality of lockingelements has the advantage that a very solid vertical locking can beprovided. Moreover, the reliability of the locking can also beincreased: if one pair of the locking elements fails, then there is atleast one other pair to compensate for this fail.

In the case that the male coupling part on the short edge is providedwith a plurality of locking elements which provide for the locking invertical direction, those preferably all are made from the material ofthe floor panel and in particular in one piece therewith.

In a practical embodiment, the male coupling part on the short edgecomprises a second locking element, which, in a coupled condition ofthis male coupling part with the female coupling part on the long edge,cooperates with a second coupling element of the respective femalecoupling part in order to effect said locking in horizontal direction.

Most appropriate, the second locking element of the male coupling parton the short edge is made from the material of the floor panel and inparticular in one piece therewith. This is possible, for example, bymanufacturing this locking element with one or more cutting tools ormilling tools from the material of the floor panel.

There, where the two locking elements cooperate with each other, theypreferably define a tangent line, which runs upward in the directionaway from the respective female coupling part. This tangent line thuspreferably is running inclined. Such configuration increases thesmoothness of interconnecting the respective coupling parts. Preferably,said tangent line forms an angle with the vertical which is smaller than45 degrees and still better is smaller than or equal to 30 degrees. Suchangle offers an excellent compromise between, on the one hand, thesmoothness of installation and, on the other hand, the strength of thehorizontal locking.

A particularly preferred embodiment shows at least the followingcharacteristics:

-   -   the male coupling part on the short edge comprises the already        mentioned first locking element, wherein this first locking        element is performed as a separate insert, which is provided in        a recess in the male coupling part; and    -   the male coupling part on the short edge comprises the already        mentioned second locking element, wherein this second locking        element is made from the material of the floor panel and in        particular is made in one piece therewith; and    -   the male coupling part on the short edge comprises a protruding        lip, wherein in a distal side or edge of this lip the recess is        provided in which the insert is situated, and wherein the second        locking element of the male coupling part on the short edge is        made in the form of a protrusion on the lower side of the        protruding lip.

Preferably, the lower side of the protruding lip, distally from theprotrusion, comprises a portion with which it rests on the femalecoupling part on the long edge in a coupled condition among thesecoupling parts. This portion is situated proximally from a closing planedefined between the respective coupled edges. Such support offers theadvantage that the risk of height differences, which might arise as aresult of the floor panels being walked on, can be minimized or evenavoided. The tangent line which is defined there, where the mentionedportion rests on the respective female coupling part, preferably isoriented horizontally or approximately horizontally.

In particular, on the lower side of the protruding lip a space ispresent between this lip and the respective female coupling part. Thisspace preferably extends continuously between said portion of theprotruding lip which rests on the female coupling part, and there, wherethe two locking elements cooperate with each other.

It is particularly advantageous when the male coupling part on the shortedge can also be inserted by means of a horizontal or approximatelyhorizontal snap movement into the female coupling part on the long edge.During such snap movement, the respective male coupling part, relativelyseen, is moved towards the female coupling part according to a directionperpendicular to the respective edges and in the plane or approximatelyin the plane of the floor panels and is inserted into the femalecoupling part with the occurrence of a snap effect. That such snapmovement is possible, offers more possibilities in respect toinstallation, as will be evident from the detailed description.

Performing the snap movement can be facilitated by providing the femalecoupling part with an elastically bendable part. This elasticallybendable part then can be elastically bent when performing the snapmovement and thus, so to speak, temporarily enlarge the opening in thefemale coupling part for inserting the male coupling part. For example,use can be made of an elastically bendable lower lip.

In order to let the second locking elements smoothly engage one behindthe other when performing the snap movement, it is advantageous toprovide an inclined guiding surface on the lower side of the malecoupling part. When performing the snap movement, this guiding surfacethen preferably cooperates with the distal end of the female couplingpart and in particular with the upper side thereof. For example, thedistal side or edge of the already mentioned protrusion on the lowerside of the male coupling part can be realized as such guiding surface.

It is also noted that the male coupling part on the short edgepreferably fits precisely into the female coupling part on the long edgeor can fit into it even with a certain play. Thus, in other words, thereis preferably no tensioning force which presses the respective short andlong edges towards each other at the upper sides thereof. This allowscompensating the possible non-perpendicularity of the floor panels.However, the invention does not exclude the presence of such tensioningforce. In the case that it is present, though, it can be realized on thebasis of the principle described in respect to FIG. 23 of document WO97/47834.

Preferably, the coupling parts on the long pair of edges respectivelyare realized in the form of a tongue and a groove which is bordered byan upper and a lower lip, wherein the tongue and groove are providedwith locking elements, which, in a coupled condition of the tongue andgroove, counteract the moving apart thereof in horizontal direction. Byhorizontal direction, here the direction is meant which is perpendicularto the respective edges and lies in the plane of the floor panels. Suchcoupling parts are known as such from, amongst others, document WO97/47834.

The lower lip preferably protrudes beyond the upper lip. It is preferredthat this lower lip comprises a locking element, which then best extendsin that portion of the lower lip which protrudes beyond the upper lip.In coupled condition, this locking element then cooperates with alocking element which is situated on the lower side of the tongue.

There, where they cooperate with each other, the locking elements on thetongue and groove preferably define a tangent line which runs upward inthe direction away from the groove. This tangent line preferably relatesto an inclined tangent line. Preferably, it forms an angle with thevertical which is smaller than 45 degrees and still better is smallerthan or equal to 30 degrees.

Preferably, the upper side of the tongue, in coupled condition,cooperates with the lower side of the upper lip. This cooperationresults in effecting a locking in vertical direction. There, where thisupper and lower side cooperate with each other, preferably a tangentline is defined which is oriented horizontally or approximatelyhorizontally.

In coupled condition, the tongue preferably extends underneath the upperlip over a distance of at least ⅙ times the overall thickness of thefloor panel. More preferably, this distance is at least ¼ times theoverall thickness of the floor panel and still more preferably even atleast ⅓ the overall thickness of the floor panel. It is clear that thisdistance herein is measured according to the direction perpendicular tothe respective edges and in the plane of the floor panels. As the tongueextends relatively far underneath the upper lip, a strong verticallocking is obtained. This strong locking certainly is desired along thecoupled long edges.

Preferably, the lower side of the tongue shows a portion with which thetongue, in coupled condition, rests on the upper side of the lower lip.This portion preferably is situated at least in part distally from aclosing plane defined between the respective coupled edges. Best, thisportion even is situated entirely distal from said closing plane. Thesupport effect provides for that the tongue cannot be pressed furtherdownward. Amongst others, this offers the advantage that the risk ofheight differences, which might arise as result of the floor panelsbeing walked on, can be minimized or even avoided.

It is also noted that the already mentioned first locking element of thefemale coupling part on the long edge preferably is formed by thedescribed upper lip.

It is also noted that the second locking element of the female couplingpart on the long edge preferably concerns the described locking elementon the groove.

The coupling parts on the pair of long edges, inclusive the lockingelements, are realized from the material of the floor panel and inparticular are made in one piece therewith.

In a particularly advantageous embodiment, the male coupling part on thelong edge can also be inserted into the female coupling part on the longedge by means of a horizontal or substantially horizontal snap movement.During such snap movement, the male coupling part, relatively seen, ismoved towards the female coupling part according to a directionperpendicular to the respective edges and in the plane or approximatelyin the plane of the floor panels, and is inserted into the femalecoupling part, with the occurrence of a snap effect. That such snapmovement is possible will offer more possibilities in respect ofinstallation, as will be evident from the detailed description.

Performing the snap movement can be facilitated by providing the femalecoupling part with an elastically bendable part. This elasticallybendable part then can be elastically bent when performing the snapmovement and thus, so to speak, temporarily increase the opening in thefemale coupling part for inserting the male coupling part therein. Forexample, use can be made of an elastically bendable lower lip.

In order to have the locking elements on the tongue and groove engageone behind the other in a smooth manner when performing the snapmovement, it is advantageous to provide an inclined guiding surface onthe lower side of the tongue. This guiding surface then, when performingthe snap movement, preferably cooperates with the distal end of thefemale coupling part and in particular with the upper side thereof.

In a particular embodiment, the coupling parts on the pair of long edgesare configured such that they, in the coupled condition, provide atensioning force pressing the coupled long edges at their upper sidestowards each other. This principle is known as such from document WO97/47834, and in the technical field is denominated with the termpretension. This pretension can be realized on the basis of theprinciple illustrated in FIG. 23 of said WO 97/47834. For example, alower lip can be applied, which, in coupled condition, is permanentlyelastically bent and thereby provides the aforementioned tensioningforce.

The female coupling part on the short edge can show one or morecharacteristics of the female coupling part on the long edge. Desirably,this female coupling part on the short edge even is realized identicallyor approximately identically to the female coupling part on the longedge.

The male coupling part on the long edge preferably can be also insertedinto the female coupling part on the short edge by means of a horizontalor substantially horizontal snap movement. As will become evident fromthe detailed description, this provides more possibilities in respect toinstallation.

The inventor has found that the present invention can be applied in aparticularly advantageous manner with floor panels having a substratewhich is realized on the basis of a synthetic material, such aspolyvinyl chloride, polyethylene, polypropylene, polyethyleneterephthalate and/or polyurethane. In fact, these floor panels have beenshown to undergo drastic dimensional changes with changing temperatures.Those may lead to a warping op the floor covering and even to the floorpanels moving out of each other. However, the risk thereof can beminimized by means of the present invention by the strong locking whichcan be provided between the edges amongst each other.

The substrate of these floor panels may or may not be multi-layered,however, preferably comprises at least a substrate layer which isrealized on the basis of a composition which shows one or more of thefollowing characteristics, as far as they are not contradictory:

-   -   The composition comprises at least a thermoplastic synthetic        material.    -   The composition comprises at least a synthetic material, such as        polyvinyl chloride, polyethylene, polypropylene, polyethylene        terephthalate, polyurethane and/or an elastomer.    -   The composition comprises one or more plasticizers in an amount        of less than 20 phr and preferably in an amount between 5 and 15        phr. In case that such an amount of plasticizers is applied,        this concerns a substrate layer of the rigid or stiff type.    -   The composition comprises one or more plasticizers in an amount        of at least 20 phr. In this case, this concerns a substrate        layer of the supple or flexible type.    -   The composition comprises an inorganic filler, such as chalk,        talc and/or limestone.    -   The composition comprises an organic filler, such as wood,        bamboo and/or cork particles.    -   The composition comprises a mineral filler, such as ceramics.    -   The composition comprises mineral fiber structures, such as        fibers of glass, talc and/or wollastonite.

It is also noted that the presence of a substrate layer of the rigidtype, i.e. with an amount of plasticizer of less than 20 phr, isbeneficial for the dimensional stability of the floor panels. In Incombination with the strong locking, this rigid substrate layer thenprovides for an extremely stable floor covering.

Possibly, the substrate layer is foamed. The advantage thereof is thatthe density of the substrate layer can be reduced. In this manner, aneconomization of raw materials and energy can be realized. Also, byfoaming the substrate layer can be given new features, such as in thefield of comfort, and even more important, in the field of dimensionalstability.

It is also noted that the substrate layer can be manufactured accordingto various possibilities. So, the substrate layer may be manufactured bymeans of strewing, extrusion, injection molding, calendering and/orcoating techniques.

The substrate can be composed of a plurality of substrate layers. Thesesubstrate layers can be realized on the basis of a composition asdescribed herein above, however, do not have to be made identical toeach other. The substrate layers may differ, for example, on the basisof the amount of applied plasticizers. Herein, this may relate to thecombination of a supple substrate layer with a rigid substrate layer.

In a particularly preferred embodiment, the floor panels are of theso-called Luxury Vinyl Tile (LVT) or Wood Plastic Composite (WPC) type.For example, this relates to floor panels which are realized such asdescribed in the document U.S. Pat. No. 9,156,233 B2.

Possibly, the substrate is provided with a reinforcement layer, such asa glass fiber cloth or a glass fleece or a glass net. This reinforcementlayer then preferably is incorporated into the substrate. This meansthat the reinforcement layer then, at the lower as well as at the upperside thereof, is bordered by the material of the substrate. Thisreinforcement layer assists in increasing the dimensional stability ofthe floor panels and thus contributes to avoiding the formation of gapsand cracks in the floor covering in herringbone pattern. It is notedthat the substrate can be provided with a plurality of reinforcementlayers, whether or not incorporated.

The thickness of the floor panels preferably is substantially, thus, forthe half thereof or more, formed by the substrate.

The thickness of the floor panels preferably is situated between 2 and 8mm and more preferably between 3 and 6 mm. This allows realizing thefloor panels sufficiently thin, while they still show sufficientstrength and stability.

Preferably, the floor panels are decorative. To this aim, they can becomposed of a substrate and a top layer situated above the substrate andcomprising a decor. This decor preferably comprises a motif or patternwhich, for example, can simulate a natural product, such as wood, stoneor ceramics. This then concerns, for example, a wood motif or pattern.This motif or pattern then can simulate, for example, wood nerves orwood pores.

The decor preferably relates to a print which, whether or not directly,is provided on an underlying layer of the floor panel. When the print isnot applied directly, it then typically is provided on a carrier sheet.This carrier sheet may concern, for example, a synthetic material film,such as a polyvinyl chloride film, polyurethane film, polypropylenefilm, polyethylene terephthalate film or polyethylene film. Preferably,the carrier sheet is connected to the substrate or another layer of thetop layer by means of a thermal lamination process. When providing theprint directly on an underlying layer of the floor panel, the so-calleddirect print, it is not excluded that it is provided on a basic layer orprimer provided on the underlying layer. For the direct print,preferably a digital printer, such as an inkjet printer, is applied.

Preferably, the top layer also comprises a translucent or transparentwear layer situated above the decor. This wear layer then forms aprotection for the decor. For example, this relates to a syntheticmaterial-based wear layer, which is applied either as a film, whether ornot together with the aforementioned printed film, for example, by meansof a thermal lamination process, or is provided in liquid condition andsubsequently is hardened on the substrate or another layer of the toplayer. In the case that the wear layer comprises a film, this preferablyconcerns a thermoplastic film, in particular a polyvinyl chloride film,a polyurethane film, a polypropylene film, a polyethylene terephthalatefilm or a polyethylene film.

The top layer can be finished with a lacquer layer, which is applied onsaid wear layer and/or said decor as a liquid layer and subsequently ishardened. Preferably, this concerns a lacquer layer which ca be hardenedby UV light or excimer radiation, or a layer which can be hardened bymeans of a temperature increase. This last-mentioned layer may make use,for example, of blocked isocyanates as cross-linkers. Preferably, alacquer layer is provided on top of the possible wear layer; however,according to an alternative, the lacquer layer can function as a wearlayer.

The top layer can also be provided with embossments, whether or notrealized in register with the decor. To this aim, a roller can beapplied, such as described as such in PCT/IB2015/055826. The embossmentsprovide the floor panels with a relief, such that they can simulate anatural structure, such as a wood structure, even better. Theimpressions can be performed, for example, according to a wood nervepattern.

Apart from the substrate and the top layer, the floor panels can alsocomprise a backing layer, which is situated underneath the substrate.The counter layer can be realized, for example, on the basis of cork oron the basis of a thermoplastic synthetic material, which preferably isof the supple type. Such rather soft counter layer can provide the floorpanels with new features, for example, in the field of comfort and soundabsorption. In particular, the counter layer forms a layer with acousticfeatures. The counter layer can contribute, for example, to thereduction of the sound production of the floor panels, for example, whenthey are walked on.

As is evident from the above, the invention primarily aims at floorpanels which are composed of a substrate, which is realized on the basisof a synthetic material, such as polyvinyl chloride, polyethylene,polypropylene, polyethylene terephthalate and/or polyurethane. However,the invention is not restricted to such floor panels. For example, it isnot excluded that the invention is applied with floor panels comprisinga wood-based substrate, such as an MDF or HDF substrate. The inventioncan also be applied to floor panels with a wood-based substrate and athere above-situated wooden top layer, such as a wood veneer top layer.This then concerns floor panels of the so-called engineered wood-type.

That the set of floor panels is suitable for forming a floor covering inherringbone pattern, implicitly implies that this set consists at leastof two types of floor panels. Herein, the coupling parts of the one typeof floor panels on the one pair of edges are mirrored in respect to thecoupling parts of the other type of floor panels on that same pair. Tobe more precise, it is the location of the coupling parts which ismirrored.

The present invention also relates to a method for installing the set offloor panels. This set consists of at least two types of floor panels,wherein the coupling parts of the one type of floor panels on one pairof edges are mirrored in respect to the coupling parts of the other typeof floor panels on that same pair. The method comprises at least thefollowing steps:

forming a first row by coupling floor panels of the first type to floorpanels of the second type, short edge against long edge; and

forming at least a second row at the first row by coupling floor panelsof the one type to floor panels of the other type, short edge againstlong edge, wherein the floor panels of the second row are installed bymeans of a single turning movement.

Applying this method offers a particularly smooth installation of thefloor covering in herringbone pattern. The floor panels of the secondrow and possible subsequent rows in fact can all be installed by onlymaking use of the user-friendly turning movement, which in the technicalfield often is referred to with the term fold-down movement. Moreover,the specific configuration of the floor panels provides for that in theresulting floor covering the risk of the occurrence of heightdifferences, the formation of gaps or cracks among the floor panels issmall or at least can be minimized.

In a practical embodiment, said second row is formed by inserting themale coupling part on the short edge of a first floor panel into thefemale coupling part on the long edge of a second floor panel in one andthe same turning movement which is used to insert the male coupling parton the long edge of the first floor panel into the female coupling parton the long or short edge of a third floor panel. Possible further rowscan also be installed or placed in this manner.

It is noted that by a horizontal locking a locking is meant which isactive in the direction perpendicular to the respective coupled edgesand in the plane of the floor panels. By a vertical locking in its turnthen a locking is meant which is active in the direction perpendicularto the plane of the floor panels.

It is also noted that the term guiding surfaces does not exclude thatthese guiding surfaces are curved. In other words, they are notnecessarily flat.

It is also noted that by the term closing plane the plane is meant that,from a top view, indicates the closure between the mutually coupledfloor panels. In particular, this relates to a vertical plane. Even withfloor panels which fit into each other with a play, such closing planestill can be defined. This then rather concerns a theoretical planeindicating the closure when these floor panels are pressed towards eachother.

It is also noted that by a turning movement a movement has to beunderstood wherein the floor panel is turned down with the male couplingpart from an inclined position in respect to the floor panel with thefemale coupling part in order to insert the male coupling part in thefemale coupling part. Herein, it is possible that in the inclinedposition the male coupling part is already partially inserted in thefemale coupling part, however, certainly not completely. By the downwardturning movement, the male coupling part then is completely insertedinto the female coupling part.

It is also noted that the floor panels, apart from their suitability forbeing installed in herringbone pattern, can also be used for installingother motifs or patterns.

It is clear that the characteristics in respect to the long edges canalso be applied to the short edges, wherein those of the short edgesthen are applied to the long edges. The characteristics which arementioned in respect to the long edges thus, in other words, can beprojected to the short edges, while those of the short edges then areprojected to the long edges.

Moreover, the invention is not restricted to oblong rectangular floorpanels, but can be applied with floor panels of any form. In thiscontext, the characteristics which are mentioned in respect to the pairof long and short edges respectively can be applied to a first pair ofedges and a second pair of edges. For example, floor panels in the shapeof a parallelogram can be applied.

It is also noted that the invention is not limited to floor panels. Itcan be applied more broadly to any type of panels, such as, for example,to wall panels.

According to a deviating aspect, the invention relates to a set of floorpanels which is suitable for forming a floor covering, wherein the floorpanels of the set are quadrangular and oblong and thus have a pair oflong sides and a pair of short sides, wherein the pair of long sides aswell as the pair of short sides is provided with mechanical couplingparts which allow coupling the floor panels to each other, wherein thefloor panels of the set have the shape of an inclined parallelogram andthe set consists of at least two types of floor panels, wherein thefloor panels of the one type, regarding their shape, are mirrored inrespect to the floor panels of the other type, and wherein the couplingparts show the following characteristics:

-   -   the coupling parts on the long sides allow coupling a long side        of a floor panel to a long side of another floor panel of the        same type, by means of a turning movement; and    -   the coupling parts on the short sides allow coupling a short        side of a floor panel to a short side of a floor panel of        another type in one and the same turning movement which is used        for coupling a long side of the first-mentioned floor panel to a        long side of another floor panel of the same type as the        first-mentioned floor panel.

This deviating aspect allows installing the floor panels of the set inherringbone pattern, by means of the fold-down technique. An importantadvantage is that, for forming this herringbone pattern, it is notnecessary that the long sides are compatible to the short ones. Due tothe parallelogram shape the herringbone pattern can be installed bycoupling the long sides of the panels of the same type to each other andby coupling the short sides of the panels of the one type to the shortsides of the panels of the other type. No long side must be coupled to ashort side.

The coupling parts on the long sides of both types of floor panelspreferably are realized in the form of a tongue and groove, wherein thegroove is limited by an upper lip and a lower lip. The lower lip mayprotrude beyond the upper lip. The tongue and groove preferably areprovided with locking elements, which, in coupled condition, counteractthe moving apart of the tongue and groove in horizontal direction. Suchcoupling parts are known as such from document WO 97/47834.

The coupling parts on the short sides of both types of floor panelspreferably are realized as a downward-directed upper hook-shaped partand an upward-directed lower hook-shaped part. The upper hook-shapedpart comprises a lip with a downward-directed locking element, and thelower hook-shaped part comprises a lip with an upward-directed lockingelement. In coupled condition, these locking elements counteract themoving apart of the hook-shaped parts in horizontal direction.

Preferably, the hook-shaped parts in coupled condition also effect avertical locking. This is preferably performed by means of a separateinsert. This insert may be made of synthetic material. The insertpreferably comprises a locking part which can be brought in a lockingposition in an elastic manner. This locking part preferably arrivesautomatically in the locking position during performing of the couplingmovement among the short sides. Such insert is known as such fromdocuments WO 2005/054599, WO 2008/068245 and WO 2009/066153.

The insert can be situated in a recess in the lower or upper hook-shapedpart. In coupled condition, it then cooperates with a locking element onthe other hook-shaped part in order to realize the vertical locking.This locking element preferably is realized in one part with the floorpanel indeed. The recess preferably is provided in the upper hook-shapedpart and then in particular in the distal side of this hook-shaped part.

It is not excluded that the vertical locking with the hook-shaped partsis realized solely by locking elements realized in one piece with thefloor panel.

It is noted that by “mechanical coupling parts” coupling parts areunderstood which allow realizing a mechanical locking. Thus, no glue orthe like is necessary for the locking. However, the use of glue is notexcluded.

It is also noted that by an “inclined parallelogram” a parallelogram isunderstood wherein the adjacent sides are different in length andenclose a non-straight angle.

The set according to the deviating aspect can show one or more of thecharacteristics which are described herein above before the introductionof this aspect, and such as far as no contradictions will arise.Primarily, this relates to the characteristics relating to the couplingparts on the long sides, the characteristics relating to the malecoupling part on the short side, which can be applied to the upperhook-shaped part of the deviating aspect, and the characteristicsrelating to the substrate, the top layer and the thickness of the floorpanels.

BRIEF DESCRIPTION OF THE DRAWINGS

With the intention of better showing the characteristics of theinvention, herein below, as an example without an limitative character,some preferred embodiments are described, with reference to theaccompanying drawings, wherein:

FIG. 1 in top view represents two floor panels from a set according tothe invention, as well as a partially finished floor covering inherringbone pattern;

FIG. 2 in an enlarged view represents a cross-section according to lineII-II in FIG. 1 and also represents how the coupling parts shown in thiscross-section can be inserted into each other;

FIG. 3 in an enlarged view represents a cross-section according to linein FIG. 1 and also represents how the coupling parts shown in thiscross-section can be inserted into each other;

FIG. 4 represents a variant of the coupling parts shown in FIG. 2;

FIG. 5 represents a method according to the invention for installing aplurality of the floor panels from FIG. 1 in herringbone pattern;

FIG. 6 in an enlarged manner and in perspective view shows what isindicated by F6 in FIG. 5;

FIG. 7 represents an alternative of the method from FIG. 5;

FIG. 8 in top view represents a floor covering in herringbone patternwhich is realized by means of the set of floor panels according to thedeviating aspect of the invention;

FIG. 9 in an enlarged view represents a cross-section according to lineIX-IX in FIG. 8;

FIG. 10 in an enlarged view represents a cross-section according to lineX-X in FIG. 8;

FIG. 11 represents how the floor panels of FIG. 8 can be coupled;

FIG. 12 represents a variant of the coupling parts represented in FIG.3; and

FIG. 13 represents a variant of the coupling parts represented in FIG.2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

FIG. 1 in top view represents two floor panels 1A-1B from a set of floorpanels according to the invention. These floor panels 1A-1B are suitablefor forming a floor covering in herringbone pattern, as will becomeclear from the following.

In FIG. 1 also a partially finished floor covering 1 in herringbonepattern is shown. In this floor covering 1 a plurality of the floorpanels 1A-1B are used.

The floor panels 1A-1B are oblong rectangular and thus comprise a pairof long edges 2-3 and a pair of short edges 4-5. The long as well as theshort edges 2-3-4-5 are provided with mechanical coupling parts 6-7-8-9,which allow coupling a plurality of such floor panels 1A-1B to eachother. The one long edge 2 is provided with a male coupling part 6 andthe other long edge 3 is provided with a female coupling part 7. The oneshort edge 4 is provided with a male coupling part 8 and the other shortedge 5 is provided with a female coupling part 9.

From FIG. 1, it is obvious that the floor panel 1A is of another typethan the floor panel 1B. The location of the coupling parts 6-7-8-9 inthe floor panel 1A namely is mirrored in respect to the location of thecoupling parts 6-7-8-9 in the floor panel 1B.

The appearance of the mechanical coupling parts 6-7-8-9 is described bymeans of FIGS. 2 and 3.

In FIG. 2, a cross-section according to line II-II in FIG. 1 isrepresented. This figures thus shows the appearance of the couplingparts 7-8.

Moreover, FIG. 2 also represents how these coupling parts 7-8 can beinserted into each other.

The male coupling part 8 can be inserted into the female coupling part 7by means of the downward movement M.

Apart therefrom, the male coupling part 8 can be inserted into thefemale coupling part 7 in one and the same turning movement which isapplied for inserting the male coupling part 6 into the female couplingpart 7 or 9 of another floor panel. This then relates to the so-calledfold-down movement. How this coupling movement then precisely looks,will be described in greater detail by means of FIG. 6.

The male coupling part 8 can also be inserted into the female couplingpart 7 by means of a horizontal or substantially horizontal snapmovement S1.

The male coupling part 8 and the female coupling part 7 effect a lockingin horizontal direction H as well as a locking in vertical direction V.

The male coupling part 8 comprises a locking element 10 which cooperateswith the locking element 11 of the female coupling part 7 in order toeffect the locking in vertical direction V.

In the example, the locking element 10 is realized as a separate insert.There, where the insert cooperates with the locking element 11, atangent line R1 is defined, which runs upward in the direction away fromthe female coupling part 7. This tangent line R1 forms an angle A1 withthe horizontal which preferably is smaller than 45 degrees. In therepresented example, the angle A1 is approximately equal to 38 degrees.

The insert is provided in a recess 12 in the male coupling part 8. Inthe example, this recess 12 is provided in a distal side or edge 13 ofthe male coupling part 8.

The insert comprises a locking part 14, which, when performing thecoupling movement, arrives in a locking position by performing a lateralmovement. In the example, this locking part 14, via a part 15, isconnected to an attachment part 16 with which the insert is provided inthe recess 12. The part 15 is manufactured of another, more flexible ormore elastic material than the locking part 14 and the attachment part16. This part 15 allows that the locking part 14 performs said lateralmovement. This lateral movement here concerns a lateral turning orrotation movement, which in particular is dual.

In coupled condition, the locking element 22 cooperates with the lowerside of the upper lip 14. There, where they cooperate with each other, atangent line R2 is defined, which forms an angle A2 with the horizontalwith is different from zero.

The male coupling part 8 also comprises the locking element 17, whichcooperates with the locking element 18 in order to effect said lockingin horizontal direction H.

The locking element 17 is made from the material of the floor panel andin one piece therewith.

There, where the locking elements 17-18 cooperate with each other, atangent line R2 is defined, which runs upward in the direction away fromthe female coupling part 7. This tangent line R2 forms an angle A2 withthe vertical which preferably is smaller than 45 degrees and morepreferably is smaller than or equal to 30 degrees. In the representedexample, the angle A2 is approximately equal to 30 degrees.

In general, the male coupling part 8 here comprises a protruding lip 19.In the distal side or edge 13 of this lip 19, the recess 12 is provided.The locking element 17 is realized in the form of a protrusion on thelower side of the lip 19.

Distally from the protrusion, the lower side of the lip 19 comprises aportion 20 with which it rests on the female coupling part 7. Thisportion 20 is situated proximally from the closing plane V1 definedbetween the coupled edges 3 and 4.

Between the lower side of the lip 19 and the female coupling part 7 aspace 21 is present. This space 21 extends continuously between theportion 20 and there, where the locking elements 17-18 cooperate witheach other.

In the example, the male coupling part 8 fits precisely into the femalecoupling part 7. This has as a result that in this coupling there is notensioning force present which presses the edges 3-4 towards each otherat their upper sides. This has the advantage that even with non-straightfloor panels these edges 3-4 still can be coupled to each other in asmooth manner. It can even be still more advantageous that the malecoupling part 8 fits into the female coupling part 7 with a certainplay.

In FIG. 3, a cross-section is represented according to line in FIG. 1.This figure thus shows the appearance of the coupling parts 6-7.

Moreover, FIG. 3 also shows how these coupling parts 6-7 can be insertedinto each other.

The male coupling part 6 can be inserted into the female coupling part 7by means of the turning movement W.

The male coupling part 6 can also be inserted into the female couplingpart 7 by means of a horizontal or substantially horizontal snapmovement S2.

The coupling parts 6-7 are realized as a tongue 22 and a groove 23,respectively. The groove 23 is bordered by an upper lip 24 and a lowerlip 25. The tongue 22 and the groove 23 are provided with lockingelements 26-18, which counteract the moving apart of the tongue 22 andgroove 23 in horizontal direction H.

The lower lip 25 protrudes beyond the upper lip 24. In that part of thelower lip 25 that protrudes beyond the upper lip 24, the lower lip 25comprises the locking element 18. This locking element 18 cooperateswith the locking element 26 on the lower side of the tongue.

There, where the locking elements 26-18 cooperate with each other, atangent line R3 is defined, which runs upward in the direction away fromthe groove 23. This tangent line R3 forms an angle A3 with the vertical,which preferably is smaller than 45 degrees and still more preferably issmaller than or equal to 30 degrees. In the example, the angle A3 isapproximately equal to 30 degrees.

The upper side of the tongue 22 cooperates with the lower side of theupper lip 24. There, where this upper and lower sides cooperate witheach other, a tangent line R4 is defined, which is situated horizontallyor approximately horizontally.

The tongue 22 extends underneath the upper lip 14 over a distance D1 ofat least ⅙ times the overall thickness T of the floor panel, andpreferably over a distance D1 of at least ¼ times the overall thicknessT of the floor panel and still more preferably over a distance D1 of atleast ⅓ times the overall thickness T of the floor panel. In theexample, the distance D1 is approximately ⅓ times the thickness T.

The lower side of the tongue 22 comprises a portion 27 with which thetongue 22 rests on the upper side of the lower lip 25. This portion 27is situated at least partially distally from the closing plane V1defined between the coupled edges 2-3. In the example, this portion issituated even entirely distal from the closing surface V1.

It is clear that the first locking element 11 of the female couplingpart is formed by the upper lip 24 and that the second locking element18 concerns the locking element on the lower lip 25.

The coupling parts 6-7 are realized from the material of the floor paneland in one piece therewith.

It is also noted that the coupling parts 6-7 can be configured such thatthey, in the coupled condition, provide for a tensioning force, whichpresses the coupled edges 2-3 towards each other at their upper sides.As already described in the introduction, to this aim then the principleof FIG. 23 of the document WO 97/47834 can be applied. Then, the lowerlip 25, for example, can be permanently bent downward in the coupledcondition.

In the example, the female coupling part 9 on the short edge 5 is madeidentical to the female coupling part 7 on the long edge 3. Thus, it isnot explicitly represented.

Considering that the coupling parts 7 and 9 are identical, thus the malecoupling part 6 can also be inserted into the female coupling part 9 bymeans of the turning movement W, as well as by means of the snapmovement S2.

In FIG. 4, another variant of the male coupling part 8 is represented.In this variant, the locking element 10 is realized from the material ofthe floor panel and in one piece therewith.

The floor panels 1A-1B preferably are composed at least of a substrate28 and a top layer 29 situated above the substrate 28. The substrate 28can be realized as described in the introduction and preferably isrealized on the basis of a composition which comprises at least asynthetic material, such as polyvinyl chloride, polyethylene,polypropylene, polyethylene terephthalate, polyurethane and/orelastomer. The top layer 29 preferably comprises a decor as well as atransparent or translucent wear layer situated above the decor. Thedetailed composition of the top layer 29 is not represented in FIGS. 2to 4.

The thickness T of the floor panels 1A-1B preferably is situated between2 and 8 mm, wherein a thickness T between 3 and 6 mm is even moredesirable.

How the floor covering 1 shown in FIG. 1 can be achieved will bedescribed by means of FIGS. 5 to 7.

In FIG. 5, a first possible method is shown for forming the floorcovering of FIG. 1.

Forming the first row X is performed by coupling floor panels 1A tofloor panels 1B. The short edge 4 is coupled to the long edge 3.

The second row Y is formed by coupling, in a first step S1, the floorpanels 1B with the long edge 2 to the long edge 3 and the short edge 5of the already installed floor panels 1B-1A of the first row X by meansof the turning movement W. Moreover, in that same movement W the shortedge 4 of the floor panel 1B can be coupled to the long edge 3 of thealready installed floor panel 1 A of the first row X. How theaforementioned turning movement W precisely is looking, is illustratedin FIG. 6. This figure represents to a larger scale and in perspectiveview what is indicated by F6 in FIG. 5.

In an analogous manner, in a second step S2 the floor panels 1A can beinstalled, which results in finishing the second row Y. It is clear thatfurther rows of the floor covering can be installed in the same manner.

In FIG. 7, a second possible method is shown for forming the floorcovering 1 of FIG. 1. This method is possible in that the coupling parts6-7-8-9 also allow a horizontal or approximately horizontal snapcoupling movement.

In FIG. 7, it is started with installing of an only partially finishedfirst row X of the floor covering.

Thereafter, in a step S3 already the partial installation of the secondrow Y is started. Herein, the floor panel 1B is coupled with the longedge 2 to the long edge 3 of the already installed floor panel 1B of thefirst row X by means of the turning movement W. In that same movement W,the short edge 4 of the floor panel 1B can be coupled to the long edge 3of the already installed floor panel 1A of the first row X. In ananalogous manner, the floor panel 1A in the second row Y is installed.

In a following step S4, the installation of the first row X continues.In order to install the floor panel 1A, in a convenient manner use ismade of the possibility of snapping. For example, the long edge 2 of thefloor panel 1A is snapped into the short edge 5 of the floor panel 1Bfrom the first row X, and the short edge 5 is snapped into the long edge2 of the floor panel 1B from the second row Y. According to analternative, the turn-snap technique can be applied, wherein then thelong edge 2 is coupled, via a turning movement, to the short edge of thefloor panel B from the first row X and then the short edge 5 is snappedinto the long edge 2 of the floor panel from the second row Y. Thefollowing floor panel 1B can be installed in the first row X by snappingthe long edge 3 to the short edge 4 of the then already installed floorpanel 1A.

Thereafter, one may further continue with the installation of the secondrow Y in a manner analogous to step S3.

FIG. 8 in top view shows a floor covering 30 in herringbone pattern, orat least a part of this floor covering, wherein this pattern is realizedby means of a set of floor panels 31 according to the deviating aspect.The floor panels 31 have the shape of an inclined parallelogram. Theycomprise a pair of parallel long sides 32-33 and a pair of parallelshort sides 34-35. The long sides 32-33 enclose a non-straight anglewith the short sides 34-35. The set consists of two types of floorpanels 31, namely the floor panels 31A and the floor panels 31B. Inrespect to their shape, the floor panels 31A are mirrored in respect tothe floor panels 31B. The floor panels 31, at their long as well attheir short sides 32-33-34-35, are provided with mechanical couplingparts with which the floor panels 31 are coupled to each other. The formof these coupling parts will be described in greater detail withreference to FIGS. 9 and 10. From FIG. 8 is clear that the herringbonepattern is formed without coupling a long side and a short side. Thelong sides 32-33 of the one type of floor panels 31A are coupled to eachother, the long sides 32-33 of the other type of floor panels 31B arecoupled to each other, and the short sides 34-35 of the one type offloor panels 31A are coupled to the short sides 34-35 of the other typeof floor panels 31B. Thus, there is no compatibility required betweenthe long sides 32-33 and the short sides 34-35.

FIG. 9 represents the coupling parts 36-37 on the long sides 32-33 incoupled condition. These coupling parts 36-37 allow that the long side32 of a floor panel 31A or 31B can be coupled to the long side 33 ofanother floor panel 31 of the same type by means of the turning movementW. The coupling parts 36-37 are realized as a tongue 38 and a groove 39.The groove 39 is bordered by an upper lip 40 and a lower lip 41. Thelower lip 41 protrudes beyond the distal extremity of the upper lip 40.Locking elements 42-43 are present, which provide for a locking in thehorizontal direction H. These locking elements 42-43 consist of aprotrusion 44 on the lower side of the tongue 38 and an upward-directedlocking element 45 as a component of the lower lip 41.

It is noted that the coupling parts 36-37 can also allow that the longside 32 of a floor panel 31A or 31B can be coupled to the long side 33of another floor panel 31 of the same type by means of a horizontal orsubstantially horizontal translation or snap movement S. With thismovement S a snap effect occurs. This snap effect is the result of theelastic movement EM performed by the lower lip 41 during the translationmovement S.

It is possible that the lower lip 41 in coupled condition is elasticallybent and thus provides a tensioning force which presses the long sides32-33 towards each other. This is also denominated “pretension” and isknown as such from document WO 97/47834. In FIG. 9, this is the case dueto the presence of the downward-bent lip 41.

It is also noted that it is not required that the coupling parts 36-37on the long sides 32-33 of the one type of floor panels 31A areidentical to the coupling parts 36-37 on the long sides 32-33 of theother type of floor panels 31B, which here indeed is the case. There isno compatibility required between these coupling parts, as is clear fromFIG. 8.

FIG. 10 shows the coupling parts 46-47 on the short sides 34-35 incoupled condition. These coupling parts 46-47 allow that the short side34 of a floor panel 31A or 31B can be coupled to the short side 35 of afloor panel 31 of the other type in one and the same turning movement Wwhich is used for coupling the long side 32 of the first-mentioned floorpanel 31A or 31B to the long side 33 of another floor panel 31 of thesame type as the first-mentioned floor panel 31A or 31B. The turningmovement W entails a downward coupling movement DM between the shortsides 34-35. How this precisely is functioning is illustrated in FIG.11. In this figure, the floor panel 31B to be installed is shown, aswell as the already installed panels 31A and 31B. The floor panel 31B tobe installed is brought into an inclined position, wherein the tongue 38on the side 32 of this panel 31B is partially inserted into the groove39 on the side 33 of the installed panel 31B and the coupling part 46 onthe short side 34 is situated above the coupling part 47 on the shortside 35 of the installed floor panel 31A. From this inclined position,the floor panel 31B to be installed is turned downward, according to themovement W, by which the long side 32 as well as the short side 34 ofthis panel 31B are coupled. The situation is analogous when startingfrom a floor panel 31A to be installed.

The coupling parts 46-47 are realized as a downward-directed upperhook-shaped part 48 and an upward-directed lower hook-shaped part 49.The upper hook-shaped part 48 comprises a lip 50 with adownward-directed locking element 51, and the lower hook-shaped partcomprises a lip 52 with an upward-directed locking element 53. Thelocking elements 51 and 53 provide for the locking in the horizontaldirection H.

The hook-shaped parts 48-49 also realize a locking in the direction V.To this aim, a separate insert 54 cooperates with the locking element55. The insert 54 consists of three parts: a locking part 56, aconnection part 57 and an attachment part 58. The insert is made ofsynthetic material by means of coextrusion. The connection part 57 ismade more flexible than the other parts 56 and 58. It provides for thatthe locking part 56 can be brought in the locking position in an elasticmanner. During the coupling movement, the locking part 56 performs arotational movement R and automatically arrives in the locking position.The insert 54 is provided with the attachment part 58 in the recess 59.The recess 59 is provided in the distal side 60 of the upper hook-shapedpart 48.

It is noted that the coupling parts 46-47 also allow that the short side34 of a floor panel 31A or 31B can be coupled to the short side 35 of afloor panel 31 of the other type by means of a horizontal orsubstantially horizontal translation or snap movement, wherein a snapeffect occurs with this movement. This snap effect is the result of theelastic movement performed by the lip 52 during the translationmovement.

Further, the coupling parts 46-47 also allow that the short side 34 of afloor panel 31A or 31B can be coupled to the short side 35 of a floorpanel 31 of the other type by means of a turning movement.

It is possible that the lip 52 of the lower hook-shaped part 49 incoupled condition is elastically bent and in this manner provides atensioning force pressing the short sides 34-35 towards each other. Thisis also denominated “pretension” and in such system with hook-shapedcoupling parts is known from document BE 2015/5686.

FIG. 12 represents a variant of the coupling parts 6-7 which arerepresented in FIG. 3. The contact which is formed between the lockingelements 18 and 26 is indicated by reference C1. This contact C1 isformed by locking surfaces 61-62 cooperating with each other. Theparticularity of the coupling parts 6-7 of FIG. 12 is that next to orclose to the contact C1 a contact C2 is formed. This contact C2 isformed between the lower side of the tongue 22 and the upper side of thelower lip 25. The contact C2 can be situated directly next to thecontact C1, such that actually a single contact is formed. Or, as is thecase in FIG. 12, the contact C2 can be separated from the contact C1 byan intermediate space or free space 63. In FIG. 12, the contact C2 issituated closer to the vertical closing plane V2 than the contact C1.However, in a variant the contact C2 can be situated farther from theclosing plane V2 than the contact C1. For example, the contact C1 thenis situated on the upper side of the locking element 18.

The contact C2 provides for that friction at the location of the contactC1 is counteracted. This friction implies that the locking surfaces61-62 move relatively in mutual respect. Such friction may occur, forexample, when the floor panels are walked upon. Counteracting thisfriction reduces the risk of creaking noises which may occur as a resultof the friction. This is particularly advantageous when the substrate 28is wood-based.

The presence of the contact C2 has proven particularly advantageous whena tensioning force is present in the coupling parts 6-7 which pressesthe coupled edges towards each other. In FIG. 12, this tensioning forceis provided by the downward-bent lower lip 25. The bending VM of thislip 25 is illustrated.

FIG. 13 represents a variant of the coupling parts 7-8 which arerepresented in FIG. 2. The contact which is formed between the lockingelements 17 and 18 is indicated by reference C3. This contact C3 isformed by locking surfaces 64-65 cooperating with each other. Thecoupling part 7 is made identical to the coupling part 7 of FIG. 12. Thecoupling part 8 is realized such that apart from the contact C3 acontact C4 is formed. This contact C4 is formed between the lower sideof the lip 19 and the upper side of the lower lip 25. In the example,both contacts C3 and C4 form a single contact, however, it is notexcluded that they are separated by an intermediate space or free space.Such contact C4 reduces the risk of creaking noises.

It is also noted that the variant of FIG. 12 can be applied incombination or not in combination with the one of FIG. 13.

The present invention is in no way limited to the embodiments describedherein above, on the contrary may such methods and floor panels berealized according to various variants, without leaving the scope of thepresent invention.

1. A set of floor panels suitable for forming a floor covering, whereinthe floor panels of the set are quadrangular and oblong and thus have apair of long sides and a pair of short sides wherein the pair of longsides and the pair of short sides is provided with mechanical couplingparts which allow coupling the floor panels to each other wherein thefloor panels of the set have the shape of an inclined parallelogram andthe set consists of at least two types of floor panels, wherein thefloor panels of a first type, regarding their shape, are mirrored inrespect to the floor panels of a second type, and wherein the couplingparts show the following characteristics: the coupling parts on the longsides allow coupling a long side of a floor panel to a long side ofanother floor panel of the same type, by means of a turning movement;and the coupling parts on the short sides allow coupling a short side ofa floor panel to a short side of a floor panel of another type in oneand the same turning movement which is used for coupling a long side ofthe first floor panel to a long side of a second floor panel of the sametype as the first floor panel.
 2. The set of floor panels of claim 1,wherein the long sides of the first and second types of floor panels arerealized in the form of a tongue and groove, wherein the groove islimited by an upper lip and a lower lip, wherein the lower lip protrudesbeyond the upper lip.
 3. The set of floor panels of claim 2, wherein thetongue and groove are provided with locking elements, which, in coupledcondition, counteract the moving apart of the tongue and groove inhorizontal direction.
 4. The set of floor panels of claim 1, wherein thecoupling parts on the short sides of the first and second types of floorpanels are realized as a downward-directed upper hook-shaped part and anupward-directed lower hook-shaped part, wherein the upper hook-shapedpart comprises a lip with a downward-directed locking element, and thelower hook-shaped part comprises a lip with an upward directed lockingelement, wherein, in coupled condition, said locking elements counteractthe moving apart of the hook-shaped parts in horizontal direction. 5.The set of floor panels of claim 4, wherein the hook-shaped parts incoupled condition effect a vertical locking.
 6. The set of floor panelsof claim 5, wherein said vertical locking is effected by means of aseparate insert, made of synthetic material.
 7. The set of floor panelsof claim 6, wherein said insert is situated in a recess in the upperhook-shaped part.
 8. The set of floor panels of claim 6, wherein saidinsert is situated in a recess in the lower hook-shaped part.
 9. The setof floor panels of claim 5, wherein said vertical locking is realizedsolely by locking elements realized in one piece with the floor panel.10. The set of floor panels of claim 1, wherein said floor panels arecomposed of a substrate, which is realized on a basis of a syntheticmaterial, and a top layer situated above the substrate and comprising adecor.
 11. The set of floor panels of claim 10, wherein said syntheticmaterial is polyvinyl chloride, polyethylene, polypropylene,polyethylene terephthalate or polyurethane.
 12. The set of floor panelsof claim 11, wherein said top layer comprises a translucent ortransparent wear layer situated above a decor.
 13. The set of floorpanels of claim 12, wherein a thickness of the floor panels is situatedbetween 3 and 6 mm.
 14. The set of floor panels of claim 1, wherein saidfloor panels are composed of a wood-based substrate.